Crime scene response is one of the most important and most difficult to master aspects of patrol work. The reason for this is that crime scenes are complex: They can vary in size from a single room to a couple of acres. And almost anything at a crime scene can be a piece of physical evidence.
The basic definition of a crime scene is the location where a crime occurred. What’s easy to forget, however, is that the crime scene can extend well beyond the borders of the initial or primary scene. The victim’s body, the suspect’s body, the involved vehicles, and any other location the victim or suspect were located before or after the crime are potential crime scenes that patrol officers need to identify and secure.
When patrol officers arrive at a crime scene, they have the most influence and control over the identification and preservation of all evidence related to a criminal action. This is critically important because any mistakes or omissions made early on by first responders can get magnified down the road in a criminal prosecution. Always remember, effective criminal prosecution starts the moment the first officers arrive on scene.
Let’s take a look at steps that you as patrol officers can take that will help investigators and prosecutors build a solid case. Note: This article is primarily about what you should do when responding to a major scene, but the basic principles apply to all crime scenes.
Crime Scene Priorities
You are the primary unit dispatched in response to a burglary in progress. While you are en route, dispatch airs that the homeowner and the suspect are in a struggle. Just before arriving on scene, you learn that the suspect stabbed the homeowner and fled the area on foot.
As the first responder on scene, you have a lot of tasks that you must accomplish. First and foremost, a dangerous suspect is loose in the area, so officer and public safety concerns are paramount. You have an injured victim who needs immediate medical aid. And you have to preserve the crime scene so that the suspect can be successfully prosecuted.
Rendering aid to the victim is obviously a top priority. But it’s not always easily accomplished. You have to consider whether the scene is safe enough to allow medics access to the patient. Rendering aid to the victim is paramount, but you don’t want to place other emergency personnel in harm’s way.
Once the scene is secure and medical personnel enter, try to limit access to only essential personnel. Just because 10 firefighters and five paramedics are on scene doesn’t mean that 15 people need to tromp though the scene. That said, do not limit access to emergency personnel if it restricts or limits care to the victim.
Also, to minimize contamination, consider establishing a defined route into and out of the scene for all personnel. Conduct a quick search of the area to ensure no physical evidence will be disturbed, then mark off a path in a way that responders know where they need to walk. I’ll often stake yellow tape on the ground as a guide.
I also recommend providing basic crime scene training to your local EMS personnel and first responders. A small amount of training for these fellow public safety officers can help minimize crime scene disruption at future scenes.
Bodies of Evidence
If possible, consider taking initial photographs of the victim as soon as you can. This quick case study will tell you why victim photographs taken by first responders can be critical in a criminal investigation.
In 1997, a Boulder, Colo., woman called 911 to report screams in the alley behind her home. A patrol officer arrived on the scene and discovered a severely beaten 21-year-old woman. Moments later, other officers and medical teams arrived. While the EMS personnel attended to the victim, the first officer on scene had the presence of mind to grab a camera and start snapping pictures.
The victim subsequently died from her injuries. And the photographs taken in the alley by the patrol officer were the only pictures that showed the original state of dress of the victim. The fact that her sweatshirt hood was on, and her pants were askew became important details in the case that would have been lost if the photographs hadn’t existed.
Always remember that the most critical evidence at any violent crime scene is likely to be the victim. The victim may have seen his or her attacker and is likely the only witness who is both willing and able to say what happened.
Consider assigning a patrol officer to ride in the ambulance with the victim. If the victim is critically wounded this might be the only chance to attempt an interview or record his or her statements.
Putting an officer in the ambulance also ensures a solid chain of custody for evidence on or near the victim’s body. Even the sheets covering the gurney can become evidence because of transfer from the victim to the sheets.
The suspect’s body is also one of the most critical crime scenes. Perishable evidence such as trace evidence and blood evidence need to be collected as quickly as possible.
However, there are legal concerns regarding the collection of this evidence. Consult a supervisor, department attorney, or district attorney to make certain that evidence from the suspect’s person is collected legally. If exigency doesn’t exist, draft a search warrant and/or obtain written consent.
You may even want to consider bagging the suspect’s hands if there’s any delay in collecting the evidence. Bagging hands is useful in many types of cases, including assault and sexual assault, not just in shooting cases where GSR (gun shot residue) tests are conducted.
Setting the Scene
Once aid is rendered and the crime scene is secure, it’s time to clearly define the scene boundaries. Colored crime scene tape is the most commonly used way to keep people out of the scene.
An effective patrol officer should always carry basic crime scene response equipment, including yellow crime scene tape for marking a scene. You also need basic evidence markers and a camera, and I recommend carrying an assortment of boxes or other items that can be used to protect perishable evidence if weather conditions threaten the evidence.
When taping off a scene, it’s a good idea to make it larger than you think it needs to be. Many times it’s not until later that evidence is located nearby. A weapon, footwear or tire impressions, and blood can often be found some distance away from the primary scene.